Halting and reversing upward secular trends in body weight in the US is an important medical and public health challenge. Additional skilled researchers in obesity prevention are much needed, but training programs are few. Obesity is a complex disorder that has multiple causes and multiple potential strategies for prevention and treatment. The present proposal is a competitive renewal application for a training grant called the Minnesota Obesity Prevention Training (MnOPT) program. Originally funded in 2010, its goal is to provide multidisciplinary training for a new generation of obesity prevention scientists MNOPT has successfully recruited 9 trainees over the last four years from a large pool of highly qualified applicants, six post docs and three predocs, all of whom have been matched with appropriate mentors and all of whom have been productive. We have also conducted a successful educational program with interdisciplinary training for all fellows in biological mechanisms and clinical and public health interventions as well as training in ethical conduct of research. We have directed each of the fellows to educational experiences, e.g. research design and analysis, as individually appropriate. We are proposing only minor changes to this successful program in this renewal. Because of the size and composition of the applicant pool, we are requesting two additional training slots to the five already approved and are also planning to combine the existing basic science and clinical tracks into a single training track. Robert Jeffery will remain the overall director, as well as director of the epidemiology/behavioral track, and Catherine Kotz, professor in the Department of Food Science and Nutrition, will serve as co-director and director of the basic science/clinical track. The research base at the University of Minnesota remains strong. The number of participating faculty has decreased from 36 in the original application to 33 in the current renewal to include only those with documented mentoring experience and the strongest research base. The institutional support for the training program has also strengthened since the initial proposal.